PpGal2A

Exo-Gal0252

(EC.3.2.1.23)exo-β-Galactosidase

CAZy Family: GH2

PROPERTIES

1.ELECTROPHORETIC PURITY

-Single band on SDS-gel electrophoresis (MW ~115kDa)

Figure 1. Electrophoresis analysis of PpGal2A. M, molecular weight marker (PageRuler Prestained Protein Ladder, Thermo Scientific); lane 1, culture lysate before IPTG induction; lane 2, culture lysate after IPTG induction; lane 3, PpGal2A purified from Ni sepharose fastflow column.

2.SPECIFIC ACTIVITY

1.14 U/mg protein (on pNP-β-gal) at pH 7.0 and 37°C.

One Unit of pNP-β-gal activity is defined as the amount of enzyme required to release 1 μmol of p-nitrophenyl per minute from pNP-β-gal (5 mM) in phosphate buffer (20 mM) pH 7.0.

3.RELATIVE RATES OF HYDROLYSIS OF SUBSTRATES

Table 1. Relative activity of PpGal2A on different substrates^a.

^aReactions were performed with 5mM substrate, pH 7.0, at 37°C for 5 min.

^bAbsorption caused by released p-nitrophenol was measured at 405 nm. The relative activity on pNPβGal was taken as 100%.

^cThe data are reported as means±standard errors from the mean for three independent experiments.

Figure 2.HPAEC-pulsed amperometric detection (PAD) analysis of hydrolysis products of galactobiose generated by PpGal2A

Figure 3. HPAEC-PAD analysis of the methylated products of the degradation of Galactan by PpGal2A

4.PHYSICOCHEMICAL PROPERTIES

pH Optima: 7.0

Temperature Optima: 40°C

5.STORAGE CONDITIONS

The enzyme should be stored at -20°C. For assay, this enzyme should be diluted in phosphate buffer (20 mM) pH 7.0. Swirl to mix the enzyme immediately prior to use.

6. REFERENCES

[1] 毛子寒. 多粘类芽孢杆菌中β-半乳糖苷酶的重组表达及降解果胶活性研究[D]. 东北师范大学, 2023.